New fluid head measuring system enhances product development for wetrooms

Coram UK Holding Ltd has a new bespoke test rig that enhances the accuracy and speed of measuring the drainage performance of wetroom shower drains. The Bürkert-designed automated system enables fast and precise measurement of head heights as low as five millimetres across a wide flow range. Coram UK says that the new test system has increased the ease of wetroom drain testing and has encouraged new product development as a result of the rapid, on-site testing capability.

Coram UK designs and manufactures the Impey brand of wetroom products for the healthcare sector, as well as for commercial and residential use. The Impey portfolio’s latest addition is the designer linear drain tops, laser cut from stainless steel, which require consistent water drainage performance without compromising the aesthetic design. Drain performance is measured by combining volumetric flow from a shower head with the head height of water above the drain. Meeting these levels achieves safety standards and demonstrates drainage performance to end users.

Previously, Coram UK used a manual system to measure head height when testing drain designs which required two engineers – one to control the pump and a second to take the measurement, then provide feedback regarding the required flow level. Operating the system required a level of skill and could take several hours. While this system was industry-standard and provided drain performance validation, Coram UK wanted a test rig that would enhance the ease and speed of product development. The manufacturer engaged Bürkert’s engineers to design an accurate, automatic system to save time, reduce costs and improve both accuracy and repeatability.

“It’s much faster to achieve very accurate head height and flow readings with the new test rig because the system is more sensitive to precise changes; and it records the results automatically,” says Clare Cranston, Coram UK’s Design and Development Manager. “The Bürkert system enables us to measure more accurately than we previously thought possible and is helping us to improve our product development process.”

The system needed to be compatible with any design of drain and crucially it had to be able to accurately measure a low water head height from as low as 5mm, extending through to 20mm. This ruled out technologies such as radar or ultrasonic sensors, because the resolution would not be sufficient in such shallow depths and small distances. Instead, Bürkert’s UK design team opted for a sensor based on hydrostatic technology.

“It was a challenge to achieve very precise levels of accuracy,” says Paul Trevitt, Bürkert UK’s Service & Systems Engineering Manager. “The proof was in the testing. Placing a small cloth into a cup with just 5mm head height of water, the measuring device was able to detect the absorption and the tiny change in water level.”

The system comprises a pump that generates inflow from a water tank, with a Bürkert Type 8030 flow sensor and a Type 3361 control valve, managed overall by a PLC with programming designed by Bürkert UK. This provides precise flow control from as low as 0.1 litres per second and enables Coram UK to test drains across a wide variety of flow rates, measuring the resulting water head heights accordingly. The system has also been designed to enable testing of the flow rate alone, which adds a secondary check to ensure that excess flow doesn’t impact drainage.

Results are recorded every second, meaning that Coram UK can demonstrate its drains perform over an extended duration. Data logging also gives the ability to compare design performance more accurately. Significantly, automated recording also means the system can be operated by just one engineer.

“The new system saves resources and encourages product development. We’re able to make design changes, manufacture a prototype on our 3D printer, then quickly test the new design in-house,” says David Jones, Product Designer, Coram UK. “The new system means that we can bring products to market more quickly.”

It was also a requirement that the system would be easy to use without specialist skills or training that would be better employed on other tasks. It takes a manual-free approach and has been designed to operate with the ease of a smartphone, with the user interacting with a simple touch-screen HMI. A secondary HMI with waterproof IP65 protection is also located within the actual wetroom test environment displaying live results.

“From the PLC user interface, after just five touchscreen options the test is ready to start,” says Emma Snowdon, Product Design Engineer, Coram UK. “The time saving achieved by the new system will also help reduce the cost of product development. The previous test rig was in operation for 10 years and the new automated system is futureproofed for generations of product to come.”

About Bürkert

Bürkert Fluid Control Systems is one of the leading manufacturers of control and measuring systems for fluids and gases. The products have a wide variety of applications and are used by breweries and laboratories as well as in medical engineering and space technology. The company employs over 2,200 people and has a comprehensive network of branches in 35 countries world-wide.